Changing stem from 90mm to 50mm>
 

Will be getting back on a bike after many many moons, I will have to ride a while before i get comfortable again. I like the Trek FXII Disc. 15"/S frame.
https://www.trekbikes.com/in/en_IN/b...-disc/p/23350/

I'm 5'2"/55YO and can reach the handlebars but with no bend to my arms... I kinda anticipate neck and tennis elbow issues... The salesman (owner) suggested I try the 90mm for a while and then switch if i need it...

Would it be premature to switch to a 50mm stem at the onset and just be comfortable right off the bat?
Also my standover is about an inch or so... is that okay? Didn't feel too deterred by that though.

Standover is fine. Don't worry about that.

Perfectly reasonable to put on a 50 mm stem, but I am of the school of thought that it's usually best to move handlebars upward and backward at the same time -- all things being equal. Thus, were it me, I'd throw on a riser bar at the same time, or maybe a high-rise stem, or even an adjustable stem.

I bought a used bike from a taller person, .. that's what I did..
fitted a 4 bolt face plate 5 cm stem, I had on hand..

Dealer is saying , essentially, 'try it as we got it' ,
the stem included to build up the bike, as supplied by the factory..

Up Angled short stems are a thing... as are stem raisers,

and replacing cables and housing if they, as set up in factory,
don't reach the new higher bar location....

Thanx guys. I have a better understanding of stems and raisers now. Cheers